Feature request: Geographic spot checks for expected transit service

[evansiroky]

Is your feature request related to a problem? Please describe.

Currently we sometimes may be expecting some transit service as described by GTFS to be present in a specific area, but it actually is not (see #1224 as an example).

Describe the solution you'd like

There should be a process to identify areas where transit service is expected to exist and associated automated checks to make sure the current GTFS data is present for that area.

Describe alternatives you've considered

Manually looking through routes of GTFS feeds.

Additional context

There could be a few items that should make this up:

• Airtable or some other place could have manually defined GeoJSON of where service is expected to exist
• The service area of GTFS feeds could be calculated and compared between different versions to see if there were unexpected gaps in service area coverage
• Some kind of dashboard could exist to flag areas where service is not present to data quality analysts

[evansiroky]

The analyst team was able to create a notebook or something and delivered some manual results for this. Eventually, the Transit Data Quality Team will get around to analyzing the output from the notebook.